A key cog in Stanford University’s energy-efficiency efforts is an HVAC recommissioning program for 90 of the largest buildings on campus. After systematically reviewing HVAC components, technicians will adjust or repair them to perform as designed.

“It’s trying to get the air-handlers, in general, back to their original state of performance,” says Bob Wheeler, a zone manager with Stanford’s facilities operations department responsible for 2.9 million square feet of building space. “Things drift over time. Sometimes, the maintenance aspect is to fix things that are broken or leaking. But if they’re only sort of broke or only leaking a little, they may not get that attention.”

The recommissioning team includes technicians from Stanford’s HVAC shop and an engineer from the zone-management office who acts as the team leader. The engineer works with different zone managers to identify the buildings that use the most energy.

After the team recommissions the systems in Wheeler’s buildings, he reviews the final report to better understand the team’s findings. The team might fix smaller problems during the recommissioning phase, but Wheeler and his staff are responsible for working with the team for larger repairs and modifications. At the current pace, the department will complete recommissioning on all 90 buildings by the end of 2010.

“The recommissioning program is where they’re looking at doing a number of buildings each year,” Wheeler says. “They document as-found conditions typically at the air-handler level. And then they go through a series of checks that let them see, ‘Are the valves in the system actually closing, and when they close, is there any flow? Do the valves need to be rebuilt or replaced?’

“They look at the frequency drives and how well they’re working and what maintenance may need to be done.”